Crusher lining



L. R. CRUSHER LINING Nov. 19 1957 Filed July 16, 1954 FIG'3 FIG.

INVENTOR BY V ewww@mi?#w m u s ATTORNEYS United States r'atertt 2 Claims. (Cl. 241-299) This invention relates to crusher linings, and is particularly directed to the provision of an improved structure for the concaves used in lining large gyratory Crushers.

The normal usage of rock crushers subjects the rock breaking elements to severe abrasion, and provision must be made for the replacement of the crushing surfaces when wear has become excessive. In the case of a gyratory crusher, one of the major crushing surfaces is at the interior of the crusher shell, which is lined with heavy replaceable lining elements known as concaves Usually the front surface of the concaves is hard and smooth, and has a shape conforming to a small segment of the substantially conical crusher shell. Its rear surface is provided with ribs and pads projecting therefrom which bear against the inner surface of the crusher shell. The cavities formed by the ribs are often filled with cement; and molten zinc or other low melting point metal is poured into the spaces that exist between the rear surface of the concave and the crusher shell, and there it solidilies. The zinc forms bedding layer which backs the concave and minimizes the danger of cracking under the severe crushing loads to which it is subjected. Additionally, the zinc bonds the concaves to the crusher shell.

The removal of worn concaves from a gyratory crusher is a slow and difficult operation. A common practice is to loosen the concaves by driving wedges between each concave and the crusher shell, so that they can be removed from the shell. In order to remove the rst concave from a ring of concaves, it is often necessary to burn the concave in two with a torch. T-he diiculty of this job is of such magnitude that removing the worn lining of a large gyratory crusher requires several days of laborious hand eiort.

The present invention provides an improved concave for use in lining a gyratory crusher, comprising a heavy plate having upper and lower transverse ribs integral with said plate projecting from the rear surface thereof. The upper transverse rib of the new concave is disposed adjacent the upper edge thereof, but is spaced a short distance therebelow, whereby the body of the concave plate projects above said upper rib and provides a prying surface against which a force may be exerted for removing the concave from the crusher. The lower transverse rib is disposed along the lower edge of the concave, and includes a projection which extends downwardly to below the lower edge of the rib. 'This downwardly extending propection is adapted to underlie and support the portion of the concave plate which projects above the upper transverse rib in the row of concaves next below in the crusher lining.

A gyratory crusher is lined with concaves of the new design and is provided with a zinc or other low melting point metal bedding layer in a manner generally similar to what has been customary heretofore. The space behind the portion of the concave which extends above the upper transverse rib is, however, occupied and substantially lled by the projection which extends downwardly from the lower transverse rib of the concave next above it, and this projection supports the portion of the concave plate which it underlies. Thus, upon removal of any one of the concaves, the rear surface above the upper transverse rib of the adjoining concave in the row next below is exposed and provides a surface against which a sprying force may be exerted to remove the concave.

The invention is described more in detail below with reference to the accompanying drawings showing a preferredembodment of the invention, wherein Fig. 1 is a fragmentary sectional view through a portion of a gyratory crusher shell lined with concaves accoi-.ding to the invention;

Fig. 2 is a vertical section through a gyratory crusher shell, showing how an individual concave is pried loose; and

Fig. 3 is a perspective view showing the rear of a typical concave made according to the invention.

The crusher assembly shown in Fig. 1 comprises a permanent gyratory crusher shell 5 made up of a plurality of steel segments 6 bolted or otherwise secured together. The interior of the shell is lined with an array of suitably shaped concaves 7. The front surfaces 8 of the concaves form one of the two crushing surfaces of the crusher, the other being formed by the outer surface of the mantle 9 on the gyratory eccentric shaft.

Each concave comprises a heavy body plate 10 of ferrous metal, the front surface of which is susbtantially smooth. An upper transverse rib 11 and a lower transverse rib 12, integral with the concave body plate, project from the rear surface thereof. Upper and lower pads 3 and 4, also integral with the concave body plate, project from the rear surfaces of the upper and lower transverse ribs 11 and 12, respectively. These pads bear against the interior surface of the crusher shell. The upper transverse rib 11 of each concave is adjacent to but spaced a little distance below the upper edge 13 of the concave. Thus, when each concave is laid in place a recess or space 14 is formed between the upwardly projecting edge portion of the concave plate, above the upper rib 11, and the crusher shell.

A projection 15 extends downwardly from the lower rib 12. This projection is of such shape and size as to substantially completely occupy the space behind the upper edge portion of the adjoining concave in the row of concaves next below. Its lower rear edge is advantageously rounded substantially, as indicated at 16, to facilitate insertion of the projection 15 into the spaces 14 when the concaves are installed in the crusher.

Advantageously each concave is formed with reinforcing ribs 17 intermediate the upper and lower transverse ribs 11 and 12; and vertical ribs 18 extend along each side edge and -down the centre of each concave, as best show-n in Fig. 3.

When the concaves are laid in place against the crusher shell, molten zinc 19 or equivalent low melting point metal is poured into the space between the concaves and the crusher shell. To minimize the amount of zinc required, it is conventional to ll the spaces between the ribs 11, 12, 17 and 18 with cement 2, as shown in Fig. 2. Recesses 20 may be formed in the upper and lower transverse ribs to facilitate pouring the molten zinc into place after the concaves have been set against the shell. When the zinc solidies, it forms a backing layer which provides a firm bedding to support the concaves, and it also bonds the concaves in place against the crusher shell.

In normal service, a crusher lined with concaves as above described performs in essentially the same manner as a crusher lined with heretofore conventional concaves. However, when the concaves have become worn to the point where they must be replaced, the removal of `the"shell.

theconcaves of theinvention from the crusher shell is greatlysimplied as -compared withremoval of conventional concaves. As each horizontal row of concaves is removed, the space 14 between the projecting upper edge portions of thepla-tes in the row next'below is exposed, andthe rear surface of the upwardly projecting edge portions of the plates provides a surface against which a prying vforce may lne-exerted. Thus, as 'shown in "Fig 2, a pry-bar 21 may be inserted into vthe space 14,and its'end may be forced upwardly (for example for pulling it up with a hoist hook 22) so as to pry the'concave loose from In this manner removalof the worn concaves can be etfected lrapidly and with a minimum of manual labor, and a very large portion of the time required for relining "the crusher shell may be saved.

Various modications can of course be 'made in the concaves described above without departing from the invention. For example; the concave has beenshown and described with particular reference to upper and lower transverse ribs which provide a space 14 at the upper edge of the concave and a mating projection or tongue 1S at its lower edge; but of course these can be reversed so that the space is provided at the bottom of the concave and the projection at the top. In such case removal of the concaves would be accomplished by working from bottom to top of the crusher rather than from top to bottom. Or, instead of providing the space 14 and projection 15 at the top and bottom of the concave, they can be provided at opposite side edges; so after removing a lirst concave from any horizontal row, the remainder of the concaves in that row can be pried out one after the other. In yet another possible modification, the concave may bemade without the hollowed-outspaces on either sideof the central reinforcing rib 18 and between the transverse reinforcing ribs 17. In thislatter modication the concave has the form of simply a plate with the'spacing pads 4 projecting from its back surface and with the space 14 and mating projection 15 provided as described above. All such moditications, and others that will readily occur to workers skilled in the gyratory crusher art, come 'within the scope of the claimed invention.

I claim:

1. A gyratory crusher comprising a crusher shell lined interiorly with a plurality of rows of concaves, each of said concaves comprising aheavy plate-havingupper and lower transverse ribs integral with said plate projecting from the rear surface thereof, the upper transverse rib being disposed below the upper edge of the plate, and the lower transverse rib being disposed adjacent the lower edge of the plate and being formed with an integral downwardly extending projection, and a backing layer of low melting point metal cast between the crusher shell and the rear surfaces of the concaves, the projection which extends downwardly from Vthe lower rib engaging behind and supporting the adjoining plate in the row of concaves next below v-where said adjoining plate extends above its upper transverse rib, whereby upon removal of any one of the concaves from the crusher shell the rear surface above the upper rib of the adjoining concave in the row next below is exposed and provides a surface against which a prying force may be exerted to remove said adjoining concave.

2. A gyratory crusher comprising a crusher shell lined interiorly with a plurality of rows of concaves, each of said concaves comprising a heavy plates having a transverse recessformed therein adjacent the upper edge thereof with the body of the plate overlying said recess, a transverse projection formed Aon the lower `edge of the plate and extending 'downwardly therefrom, said projection engaging in the `recessat'the upper edge of a concave in the row of concaves next below, whereby upon removal of any one'of Vthe concaves from the crusher shell the recess in'theupper edge ofthe adjoining concave in the row next below isexposed and provides a surface against which a prying'force-maybe exerted to remove said adjoining concave.

References-Cited in the Itile of this patent UNITED STATES 'PATENTS 557,216 McCully Mar. 31, 1896 1,038,794 `Sholl Sept. 17, 1912 1,187,163 *McKee June 13, 1916 2,438,049 Gruender :May 16, 1948 2,594,080 Shaftes Apr. 22, 1952 

